Sed (editor)

sed utility is using for text processing, such as strings replacements.

Sed Basic examples

• Replace all occurrences of TEXT_STRING

sed -i s/OLD_TEXT_STRING/NEW_TEXT_STRING/g file.txt

• Append a text (TEST_TO_APPEND_AT_BEGINNIG) at the beginning of a line:

sed -i s/^/TEST_TO_APPEND_AT_BEGINNIG/ file.txt

Append a spce at the beggining of lines:

sed s/^./" "/

• Append a text (TEST_TO_APPEND_AT_END) at the end of a line ($):

sed -i s/$/TEST_TO_APPEND_AT_END/ file.txt

• Move N lines from text file to new file:

head -1000 input > output && sed -i '1,+999d' input

• Add at the beginning and end of a sentence:

  <code> and </code>

sed s/'^'/'\<code\>'/ | sed s/'$'/'\<\/code\>'/

• Replace spaces:

 sed s/' '//g

Related commands

• awk
• lineinfile (Ansible)
• Concatenate lines on a file using tr
• cat your_file.txt | while read i; do echo "YOUR_TEST $i"; done
• cat your_file.txt | while read i; do echo "$(date) $i"; done

See also

• Editors: vi, vim, sed, awk, emacs, lineinfile (Ansible), Atom, paste, Neovim, Rider, visudo, vipw, update-alternatives, nano, more, less, .vimrc, set (vi) zed
• ack, ag, grep, egrep, fgrep, agrep, ngrep, pgrep, awk, sed, strings, tr, tail, mtail, git grep, wc, uniq, LogQL, findstr (Windows), rg, git-grep, cut
• Ansible lineinfile module

https://stackoverflow.com/a/801036